There is known a method for assembling vessels of the above-mentioned types (cf. Japanese Patent No. 51-40359, Cl. 84K1 of 1976).
According to this method, a hull is assembled in a dry dock composed of a main chamber and a side chamber. The main chamber comprises a rear area, a middle area, and a front area bordering on the harborage area.
In the rear area of the main chamber, sections and modules are assembled with the aid of dock cranes into a parallel middlebody to be transferred to the middle area of the dock's main chamber.
The assembly of the parallel middlebody is accompanied by the assembly of the aft end in the side chamber; upon completion, the aft end, too, is moved to the middle area of the main chamber.
The aft end is then joined to the parallel middlebody. The previously assembled vessel is removed from the front area of the dock's main chamber to the harborage area, and its place is occupied by the new hull with only the fore end missing.
The front area is used to assemble the fore end and join it to the rest of the hull, whereupon the new vessel leaves the dock.
As work is underway in the front area of the main chamber, its middle and rear areas and the side chamber are used for the assembly of other vessels and their sections.
The method under review makes it possible to use a single dock for simultaneous assembly of three vessels of different degrees of completion. Different versions of this method are extensively used at a great number of shipyards.
However, the assembly of superships with the use of this method calls for very long, and thus very expensive, docks.